
import java.util.*;public class practice6
{
	public static void main(String[] args)
	{
		String a="hello world";
		System.out.println(a);
		Scanner in=new Scanner(System.in);
		String b=in.nextLine();//读一行
		System.out.println(b);
		String c=in.next();//读一个，空格后不读
		System.out.println(c);
		System.out.println(a==b);//flast
		System.out.println(a.substring(0,8));//获取子串,空格也算一个字符
	char x=a.charAt(3);//读取字符
	int y=a.length();//获取长度
	System.out.println(x);
	System.out.println(y);
	}
}
